Been with Pricegrabber over 5 years. We had tweaked our feed to send very little product to them, conversion rate just wasn't there. We reset our filter a couple weeks back as an experiment and let more product flow through and just now I started looking closely at our in-house tracking log.

I see strange bursts of traffic on various items, a lot of it originating from a facebook URL that was not a proper referrer and the IP address was always the same. This seems strange since the end-user's browser, in most, not all cases, should reflect the user's IP. Facebook isn't functioning as an ISP and proxying the end-users connection, unless something funky is going on with frames, etc.?

Also seeing lots of clicks from sources where there is NO referrer info, and IP address repeats. Yes, I know not all clients will properly send that info, but in my 15+ years experience on the net, it has always been a very very small minority of clients.

No way to tell if Pricegrabber is doing any funny business to increase sales but I think in most these situations it is affliliates playing games to make more money and sites like Pricegrabber don't care as it makes them money. At least they don't care until someone blows the horn on them sort of like the Google Adwords Class Action Lawsuit.

The data is looking VERY fishy to me. Not sure if it is a coincidence with the Facebook IPO but I wouldn't rule out the possibility of Facebook trying to pad their ad revenues so the figures look better when they try to report them to the public for the first time.

We have the same products advertised on Google Shopping and the overall conversion rate is about 20+ times higher than Pricegrabber. Even Nextag has significantly higher conversion than Pricegrabber although much lower than Google. We dumped Shopzilla a long time ago due to declining ROI. Are these price comparison engines trying to get "creative" to stay alive considering most people use Google Shopping for comparison and with algo changes on Google burying these guys, they have lost a lot of exposure in recent months/years?

I couldn't agree with you more. Pricegrabber uses questionable tactics to send clicks to their merchants and overcharge them. If properly investigated I am sure the company will be found to be committing click fraud. If you are a new merchant thinking of advertising on PG, please beware. They have 3rd party affiliate sites that send clicks to your site and most of these are fraudulent clicks. I was not properly monitoring my PG account and allowed them to charge me exorbitantly for fraudulent clicks for several months. We had 12,000 clicks on 1 product in a month, and had not a single sale on that product. The next product after that got only 80 clicks. The same product previous month had 60 clicks. What is the reason for this sudden spike (200 fold). PG doesn't know. They told me these clicks came from one of their "affiliate" sites. I looked at the IP addresses and they look like proxy servers. The clicks were most likely generated by bots. If you are advertising PPC, beware of PG. I have had similar experience with Nextag before and I stopped advertising with them too. These companies don't do anything to prevent click fraud committed by their affiliates. They don't even give you the option to opt out of their affiliates. I want to advertise on PG only. But thats not an option. You may be getting hundreds of clicks from questionable sites that are "affiliated" with PG, and PG will be charging your credit card for it. Not worth it. My honest advice: spend some money on SEO, and if you have to do PPC, do Google Adwords (even though their rates are much higher, they have very strict security measures against click fraud).